Service providers in general and mobile network operators (MNOs) in particular provide a range of communications' services to corresponding subscribers. Such services include, for example, voice, voice over Internet Protocol (IP), voice over long term evolution (LTE), streaming, broadcasting, multicasting, or other services. In providing such services, service providers typically implement different functionalities, e.g., billing functionalities, quality of service (QoS) functionalities, etc., to manage the offered services and the corresponding usage by subscribers.
In order to expand geographical coverage of offered services beyond the network coverage of each service provider, service providers typically engage in interworking and roaming arrangements. The interworking and roaming arrangements between different service providers are made possible through interconnection between the service providers. Interconnection between service providers is typically realized through one or more inter-service provider systems. Given that the Internet Protocol (IP) is widely employed across different communication networks and different services associated with service providers, the inter-service provider systems are typically designed to provide interconnection between different service providers at the IP traffic level, and to employ IP addressing. Examples of such inter-service provider systems include General Packet Radio Service (GPRS) Roaming eXchange (GRX) networks and IP Packet eXchange (IPX) networks. Interconnection between service providers may be achieved through an inter-service provider IP backbone, which represents a collection of GRX and/or IPX networks.